The investigation of fish parasites in Bosnia and Herzegovina in recent years became significant, and therefore new records of parasitic trematodes and their hosts are important for better understanding of fish parasitology and pathology. In this study 41 parasitic specimens were collected and the basic taxonomical characters were measured (body length and width, diameter of oral and ventral sucker, length and width of pharynx, ovary length and width, testes length and width and eggs length and width). After the sampling of the parasites, they were collected and conserved in 70% ethanol. After that procedure the aforementioned characters were measured using Digimizer Image Analyzer Version 4.1. After all measurements, the trematode parasite